[PATCH net-next v2 6/6] net: dsa: b53: remove eee_enabled/eee_active in b53_get_mac_eee()

[Vladimir Oltean]

On Sun, Feb 04, 2024 at 12:13:28PM +0000, Russell King (Oracle) wrote:
> b53_get_mac_eee() sets both eee_enabled and eee_active, and then
> returns zero.
> 
> dsa_slave_get_eee(), which calls this function, will then continue to
> call phylink_ethtool_get_eee(), which will return -EOPNOTSUPP if there
> is no PHY present, otherwise calling phy_ethtool_get_eee() which in
> turn will call genphy_c45_ethtool_get_eee().

Nitpick: If you need to resend, the function name changed to
dsa_user_get_eee().

> 
> genphy_c45_ethtool_get_eee() will overwrite eee_enabled and eee_active
> with its own interpretation from the PHYs settings and negotiation
> result.
> 
> Thus, when there is no PHY, dsa_slave_get_eee() will fail with

Here too.

> -EOPNOTSUPP, meaning eee_enabled and eee_active will not be returned to
> userspace. When there is a PHY, eee_enabled and eee_active will be
> overwritten by phylib, making the setting of these members in
> b53_get_mac_eee() entirely unnecessary.
> 
> Remove this code, thus simplifying b53_get_mac_eee().
> 
> Reviewed-by: Andrew Lunn <andrew at lunn.ch>
> Reviewed-by: Florian Fainelli <florian.fainelli at broadcom.com>
> Signed-off-by: Russell King (Oracle) <rmk+kernel at armlinux.org.uk>
> ---
>  drivers/net/dsa/b53/b53_common.c | 6 ------
>  1 file changed, 6 deletions(-)
> 
> diff --git a/drivers/net/dsa/b53/b53_common.c b/drivers/net/dsa/b53/b53_common.c
> index adc93abf4551..9e4c9bd6abcc 100644
> --- a/drivers/net/dsa/b53/b53_common.c
> +++ b/drivers/net/dsa/b53/b53_common.c
> @@ -2227,16 +2227,10 @@ EXPORT_SYMBOL(b53_eee_init);
>  int b53_get_mac_eee(struct dsa_switch *ds, int port, struct ethtool_keee *e)
>  {
>  	struct b53_device *dev = ds->priv;
> -	struct ethtool_keee *p = &dev->ports[port].eee;
> -	u16 reg;
>  
>  	if (is5325(dev) || is5365(dev))
>  		return -EOPNOTSUPP;
>  
> -	b53_read16(dev, B53_EEE_PAGE, B53_EEE_LPI_INDICATE, &reg);
> -	e->eee_enabled = p->eee_enabled;
> -	e->eee_active = !!(reg & BIT(port));
> -

I know next to nothing about EEE and especially the implementation on
Broadcom switches. But is the information brought by B53_EEE_LPI_INDICATE
completely redundant? Is it actually in the system's best interest to
ignore it?

>  	return 0;
>  }
>  EXPORT_SYMBOL(b53_get_mac_eee);
> -- 
> 2.30.2
>